The complete mitochondrial genome of the Forrest's rock squirrel (Sciurotamias forresti, Rodentia: Sciuridae) and its phylogenetic implication

Abstract

We sequenced the whole mitochondrial genome of Sciurotamias forresti using Illumina, revealing a 16,534 bp circular genome with 13 protein-coding genes (PCGs), 22 tRNAs, 2 rRNAs, a D-loop, and OL. Base composition: 32.95% A, 28.63% T, 26.14% C, 12.28% G. Phylogenetic analysis of 25 Sciuridae species showed a deep split between Sciurotamias forresti and Sciurotamias davidianus, more distant than those between other genera in the subfamily Xerinae. This supports the notion that Sciurotamias forresti may be ranked as a genus and indicated the necessity of further studies integrating morphological comparison and divergence dating to reevaluate its taxonomic position.

Keywords: Mitochondrial genome; Rupestes; phylogeny; south-west mountains of China.

Figure 1.

Skull and morphological appearance of Sciurotamias forresti (voucher number: BC2105059, Dali University). The photo was taken by Mengru Xie.

Figure 2.

The diagram illustrating the circular structure of the mitochondrial genome of Sciurotamia forresti. The innermost ring of the figure shows GC content, and the two vectors within and outside the scale bar show gene transcription inside and outside the circle.

Figure 3.

Phylogenetic analysis of 25 representative species using maximum-likelihood (ML) in PhyloSuite (v1.2.3) with 10,000 bootstrap replicates. Bootstrap values are indicated below the respective branches. The scale bar denotes the number of nucleotide substitutions per site. The mitochondrial genome sequence of Sciurotamias forresti (NCBI accession number: PP175169) obtained in the present study and the following sequences acquired from the NCBI database were used to reconstruct the phylogenetic tree: KM502568 Callosciurus erythraeus (Hu et al. 2016), JX572159 Petaurista hainana (Kong et al. 2015), KY070151 Tamias striatus (Sarver et al. 2017), KY070143 Tamias rufus (Sarver et al. 2017), KY070144 Tamias canipes (Sarver et al. 2017), MK859897 Marmota vancouverensis (Hao and Cao 2019), JX069958 Marmota himalayana (Chao et al. 2014), OQ675160 Spermophilus taurensis (Matrosova et al. 2023), KP698974 Ictidomys tridecemlineatus (Zhang et al. 2016), KC447304 Dremomys rufigenis, KF575124 Ratufa bicolor, JQ743657 Petaurista alborufus, KP708708 Sciurotamias davidianus, KP708706 Spermophilus dauricus, PP542035 Tamias sibiricus, KP698975 Callospermophilus lateralis, OR085844 Marmota baibacina, OR085846 Marmota sibirica, PQ533849 Spermophilus citellus, KP708706 Spermophilus dauricus, OQ835380 Spermophilus alashanicus, KP698976 Urocitellus richardsonii, MN935780 Urocitellus parryii, MT765123 Cynomys ludovicianus, KP326309 Cynomys leucurus (unpublished). Framed sample represents the target species of this study.